204 research outputs found

    Early Holocene fauna from a new subfossil site: A first assessment from Christmas River, south central Madagascar

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    We report on faunal remains recovered during recent explorations at ‘Christmas River’, the only subfossil locality known from Madagascar’s south central plateau. Recovered remains of several extinct taxa date to approximately 10,000 14C years before present (BP), including crocodiles, tortoises, the elephant bird Aepyornis, the carnivoran Cryptoprocta spelea, the lemurs Archaeolemur majori, Pachylemur insignis, and Megaladapis edwardsi, and abundant remains of the dwarf hippopotamus, Hippopotamus lemerlei. The presence of southern - limited, forest - dependent species at Christmas River supports the hypothesis that forest once extended, perhaps discontinuously, across the central highlands towards the west. One theory is that sites in the north central highlands, which are higher in elevation, maintained more mesic conditions during Plio - Quaternary climate shifts than those of the lower elevation sites of the south central highlands. Thus, elevation above sea level may have acted as a filter that limited species dispersal across the island in the past. Such a scenario would explain the distinction between more humid, higher elevation, northern highland subfossil communities versus more arid, lower elevation, southern subfossil communities. Continued exploration at Christmas River thus provides a remarkable opportunity for deciphering ecological changes that have taken place in south central Madagascar during the Holocene.RÉSUMÉMadagascar est reconnue comme l’une des régions les plus sensibles du monde en ce qui concerne les menaces pesant sur sa biodiversité, et cela à cause de niveaux d’endémisme inégalés, d’une diversité variée et d’un impact humain important sur l’environnement. Suite à la colonisation par l’Homme il y a plus de 2000 ans, des extinctions de masse de la faune et un important recul forestier ont eu lieu en laissant des marques sur les écosystèmes modernes qui sont dans un état de bouleversement écologique. Certaines plantes endémiques, par exemple, ont perdu d’importantes espèces mutualistes, des animaux ont été obligés d’exploiter d’autres ressources ou habiter des endroits auxquels ils sont mal adaptés. La diversité des plantes et des animaux a diminué, est menacée ou a même complètement disparue de certaines routes de dissémination. Bien que l’Homme soit largement incriminé dans son rôle de déclencheur de ces extinctions massives, les transformations anthropiques qui ont contribué au changement du climat sont controversées. Les hautes - terres de Madagascar sont actuellement dominées par des zones herbeuses étendues qui agissent comme des barrières empêchant les mouvements de la faune de part et d’autre de l’île. Nous suggérons qu’une forêt humide plus ou moins continue devait s’étendre sur les hautes-terres. Des informations paléoécologiques des hautes - terres du Centre sud sontènécessaires pour évaluer cette hypothèse afin de démêler la contribution relative des facteurs climatiques et anthropiques dans les changements paléoécologiques de la région. Cependant, les stations de subfossiles étaient jusqu’alors inconnues dans cette région. Nous présentons ici les résultats de recherches réalisées sur les restes fauniques découverts au cours de fouilles récentes à Christmas River, la seule station de subfossiles connue des hautes - terres du Centre sud de Madagascar. Des restes de plusieurs espèces datant approximativement de 10,000 14C B.P. ont été identifiés dont des restes appartenant à des espèces de crocodile, de tortue, de l’Aepyornis, du carnivore Cryptoprocta spelea, des lémuriens Archaeolemur majori, Pachylemur insignis et Megaladapis edwardsi ainsi que de nombreux restes de l’hippopotame nain Hippopotamus lemerlei. La présence à Christmas River d’espèces sylvicoles endémiques du Sud appuie l’hypothèse de l’existence d’une forêt, certainement discontinue, mais qui s’étendait sur les hautes - terres centrales en se poursuivant vers l’ouest. Une théorie a proposé que les sites septentrionaux des hautes - terres centrales, à des altitudes plus élevées, maintenaient des conditions plus humides au cours des changements du Plio - quaternaire que les sites méridionaux de ces hautes - terres centrales. Ainsi, dans le passé, l’altitude a du agir comme un filtre qui empêchait la dispersion des espèces d’un endroit à l’autre de l’île. Un tel scénario expliquerait la distinction entre les communautés subfossiles du nord des hautes - terres qui étaient plus humides à haute altitude et les communautés subfossiles du sud aride à basse altitude. La poursuite de l’exploration à Christmas River constitue une occasion unique pour décoder les changements écologiques qui sont intervenus dans le Sud de cette région centrale de Madagascar au cours de l’Holocène

    Incipient Social Groups: An Analysis via In-Vivo Behavioral Tracking

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    Social psychology is fundamentally the study of individuals in groups, yet there remain basic unanswered questions about group formation, structure, and change. We argue that the problem is methodological. Until recently, there was no way to track who was interacting with whom with anything approximating valid resolution and scale. In the current study we describe a new method that applies recent advances in image-based tracking to study incipient group formation and evolution with experimental precision and control. In this method, which we term "in vivo behavioral tracking," we track individuals' movements with a high definition video camera mounted atop a large field laboratory. We report results of an initial study that quantifies the composition, structure, and size of the incipient groups. We also apply in-vivo spatial tracking to study participants' tendency to cooperate as a function of their embeddedness in those crowds. We find that participants form groups of seven on average, are more likely to approach others of similar attractiveness and (to a lesser extent) gender, and that participants' gender and attractiveness are both associated with their proximity to the spatial center of groups (such that women and attractive individuals are more likely than men and unattractive individuals to end up in the center of their groups). Furthermore, participants' proximity to others early in the study predicted the effort they exerted in a subsequent cooperative task, suggesting that submergence in a crowd may predict social loafing. We conclude that in vivo behavioral tracking is a uniquely powerful new tool for answering longstanding, fundamental questions about group dynamics

    Nurse-Led Medicines' Monitoring for Patients with Dementia in Care Homes: A Pragmatic Cohort Stepped Wedge Cluster Randomised Trial

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    People with dementia are susceptible to adverse drug reactions (ADRs). However, they are not always closely monitored for potential problems relating to their medicines: structured nurse-led ADR Profiles have the potential to address this care gap. We aimed to assess the number and nature of clinical problems identified and addressed and changes in prescribing following introduction of nurse-led medicines' monitoring.Pragmatic cohort stepped-wedge cluster Randomised Controlled Trial (RCT) of structured nurse-led medicines' monitoring versus usual care.Five UK private sector care homes.41 service users, taking at least one antipsychotic, antidepressant or anti-epileptic medicine.Nurses completed the West Wales ADR (WWADR) Profile for Mental Health Medicines with each participant according to trial step.Problems addressed and changes in medicines prescribed.Information was collected from participants' notes before randomisation and after each of five monthly trial steps. The impact of the Profile on problems found, actions taken and reduction in mental health medicines was explored in multivariate analyses, accounting for data collection step and site.Five of 10 sites and 43 of 49 service users approached participated. Profile administration increased the number of problems addressed from a mean of 6.02 [SD 2.92] to 9.86 [4.48], effect size 3.84, 95% CI 2.57-4.11, P <0.001. For example, pain was more likely to be treated (adjusted Odds Ratio [aOR] 3.84, 1.78-8.30), and more patients attended dentists and opticians (aOR 52.76 [11.80-235.90] and 5.12 [1.45-18.03] respectively). Profile use was associated with reduction in mental health medicines (aOR 4.45, 1.15-17.22).The WWADR Profile for Mental Health Medicines can improve the quality and safety of care, and warrants further investigation as a strategy to mitigate the known adverse effects of prescribed medicines.ISRCTN 48133332

    Fish Intelligence, Sentience and Ethics

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    Fish are one of the most highly utilised vertebrate taxa by humans; they are harvested from wild stocks as part of global fishing industries, grown under intensive aquaculture conditions, are the most common pet and are widely used for scientific research. But fish are seldom afforded the same level of compassion or welfare as warm-blooded vertebrates. Part of the problem is the large gap between people’s perception of fish intelligence and the scientific reality. This is an important issue because public perception guides government policy. The perception of an animal’s intelligence often drives our decision whether or not to include them in our moral circle. From a welfare perspective, most researchers would suggest that if an animal is sentient, then it can most likely suffer and should therefore be offered some form of formal protection. There has been a debate about fish welfare for decades which centres on the question of whether they are sentient or conscious. The implications for affording the same level of protection to fish as other vertebrates are great, not least because of fishing-related industries. Here, I review the current state of knowledge of fish cognition starting with their sensory perception and moving on to cognition. The review reveals that fish perception and cognitive abilities often match or exceed other vertebrates. A review of the evidence for pain perception strongly suggests that fish experience pain in a manner similar to the rest of the vertebrates. Although scientists cannot provide a definitive answer on the level of consciousness for any nonhuman vertebrate, the extensive evidence of fish behavioural and cognitive sophistication and pain perception suggests that best practice would be to lend fish the same level of protection as any other vertebrate

    Urban Biodiversity and Landscape Ecology: Patterns, Processes and Planning

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    Effective planning for biodiversity in cities and towns is increasingly important as urban areas and their human populations grow, both to achieve conservation goals and because ecological communities support services on which humans depend. Landscape ecology provides important frameworks for understanding and conserving urban biodiversity both within cities and considering whole cities in their regional context, and has played an important role in the development of a substantial and expanding body of knowledge about urban landscapes and communities. Characteristics of the whole city including size, overall amount of green space, age and regional context are important considerations for understanding and planning for biotic assemblages at the scale of entire cities, but have received relatively little research attention. Studies of biodiversity within cities are more abundant and show that longstanding principles regarding how patch size, configuration and composition influence biodiversity apply to urban areas as they do in other habitats. However, the fine spatial scales at which urban areas are fragmented and the altered temporal dynamics compared to non-urban areas indicate a need to apply hierarchical multi-scalar landscape ecology models to urban environments. Transferring results from landscape-scale urban biodiversity research into planning remains challenging, not least because of the requirements for urban green space to provide multiple functions. An increasing array of tools is available to meet this challenge and increasingly requires ecologists to work with planners to address biodiversity challenges. Biodiversity conservation and enhancement is just one strand in urban planning, but is increasingly important in a rapidly urbanising world

    Aggregation tests identify new gene associations with breast cancer in populations with diverse ancestry.

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    BACKGROUND: Low-frequency variants play an important role in breast cancer (BC) susceptibility. Gene-based methods can increase power by combining multiple variants in the same gene and help identify target genes. METHODS: We evaluated the potential of gene-based aggregation in the Breast Cancer Association Consortium cohorts including 83,471 cases and 59,199 controls. Low-frequency variants were aggregated for individual genes' coding and regulatory regions. Association results in European ancestry samples were compared to single-marker association results in the same cohort. Gene-based associations were also combined in meta-analysis across individuals with European, Asian, African, and Latin American and Hispanic ancestry. RESULTS: In European ancestry samples, 14 genes were significantly associated (q < 0.05) with BC. Of those, two genes, FMNL3 (P = 6.11 × 10-6) and AC058822.1 (P = 1.47 × 10-4), represent new associations. High FMNL3 expression has previously been linked to poor prognosis in several other cancers. Meta-analysis of samples with diverse ancestry discovered further associations including established candidate genes ESR1 and CBLB. Furthermore, literature review and database query found further support for a biologically plausible link with cancer for genes CBLB, FMNL3, FGFR2, LSP1, MAP3K1, and SRGAP2C. CONCLUSIONS: Using extended gene-based aggregation tests including coding and regulatory variation, we report identification of plausible target genes for previously identified single-marker associations with BC as well as the discovery of novel genes implicated in BC development. Including multi ancestral cohorts in this study enabled the identification of otherwise missed disease associations as ESR1 (P = 1.31 × 10-5), demonstrating the importance of diversifying study cohorts

    Climate Change, Coral Reef Ecosystems, and Management Options for Marine Protected Areas

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    Marine protected areas (MPAs) provide place-based management of marine ecosystems through various degrees and types of protective actions. Habitats such as coral reefs are especially susceptible to degradation resulting from climate change, as evidenced by mass bleaching events over the past two decades. Marine ecosystems are being altered by direct effects of climate change including ocean warming, ocean acidification, rising sea level, changing circulation patterns, increasing severity of storms, and changing freshwater influxes. As impacts of climate change strengthen they may exacerbate effects of existing stressors and require new or modified management approaches; MPA networks are generally accepted as an improvement over individual MPAs to address multiple threats to the marine environment. While MPA networks are considered a potentially effective management approach for conserving marine biodiversity, they should be established in conjunction with other management strategies, such as fisheries regulations and reductions of nutrients and other forms of land-based pollution. Information about interactions between climate change and more “traditional” stressors is limited. MPA managers are faced with high levels of uncertainty about likely outcomes of management actions because climate change impacts have strong interactions with existing stressors, such as land-based sources of pollution, overfishing and destructive fishing practices, invasive species, and diseases. Management options include ameliorating existing stressors, protecting potentially resilient areas, developing networks of MPAs, and integrating climate change into MPA planning, management, and evaluation
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